Method of pallet stone cutting and polishing



R. B. MENTZER METHOD OF PALLET STONE CUTTING AND POLISHING Jan. 11, 1949.

2 Sheets-Sheet 1 Filed June 19, 1946 Fig. 4.

INVENTOR.

RALPH B. MENTZER Jan. 11, 1949. R. B. MENTZER" METHOD QF PALLET TONE CUTTING AND POLISHING Filed June 19., 1946 2 Sheets-Sheet 2 m I fl 51 on m t on 2 m3. 2. me u oe 6.1:. 92m

C Nm o I :30 5 m 3 F 2 mm ,INVENTOR.

- RALPH B. MENTZER ATTY.

PatentedJan.1l, l949 f 7 2,458,913

Mn'rnonon PALLET S TONECiUTT'ING "'ANDPOLISH-ING. g

Application June 19,1946, efriai ndlfevmiz roman. (Cl. fi+2183 This invention relates to a method forfinishing Figure 6is an. end- View. partly in section of pallet stones and particularly to the method of th e lapping machine'shown in Figure 5. supporting. the pallet stones in aposition to be Figural? is an enlarged perspective. view of a werkeduno i ii e s d e .allet stones for watches areusually finished on 5 j The holder which constitutes the invention is eight difierent surfaces, fiveof which are accom substantially a. flat disc I having a plurality of plished, without resettingwhile in this, especial ra i stalls} directly adjacent the periphery holder. This is particularly important as the ofsald disc; which stalls are adapted to receive pallets torres thenrselyes are so small as to make andsupport a pluralitypf pallet stones 3 which it necessary to mount them in shellac or some 10;- are held in their respective stalls through the holding medium inorder to. workon the surfaces. of an adhesive such as shellac. While The advantage of being ableto finishasrnany surv) nthe stalls the stones present five faces faces as possible while holding he pallet stone which can be surfaced without being removed in identically the same position i's therfore apparfrom the holder 2. Two of these operations are m sh wn n resi, 5and 6, the other operations The object of this invention is to provide a bein accomplished on conventional equipment. hglder for a plurality of palletsto nes and which "Referrin particularly tolii'gure '7 which is an will' ret'airr'said stones during jfinishing 'of the enlarged view'of a pallet'stone and shows the cr tical surfaces'of the stones. & qes whichare finished while in the holder ri g the subject of this invention. In Figure '7 nglesfare slightly exaggeratedin order to A'furtherobject of the present invention is to provide a holder for a plurality of pallet stones in b which eachstone' is"engaged,by Ithe surfacing explain their significance and the purpose machine atexactly the same angle as a similar accomplished by the cutting and finishing of the stone in adiiierent position in'theholder. surfaces. p 1

1} still furflier 'obj'ec't of. the Present invention Sides li and 5 as wjel l as the bottom 6 engage is to provide a holder in which surface finishing the sides'fand bottom oithe holder stalls and are of at least five surfaces of a palletstone without M ghl'y held by shellac, the sides of the stalls removal from the holderd yvithout forming ng sufficientlylow to allow the top edge 8 ui- 54 c meiki ss nihefl sassr aois tdnrqie t cons dera bov the sides of e stones'is possible. stalls. Thisp'ermits' the grinding and polishing of A still further object of the present invention the lead angle 9. The back end 10 and the front is to provide a holder for a plurality of pallet end II project beyond the stalls to permitengagestones which will support the stones in a position ment with the grinding wheel or lap. The rounded to be worked upon by the machine to produce surface l2 of the front end H is formed by holdidentical finished surfaces on the stones. ing a lapping medium against that edge while With the foregoing and other objects in view, rotating the holder. the invention resides in the novel arrangement In the making of identical parts for watches so and combination of parts and in the .details of that like parts may be freely interchanged the construction hereinafter described and claimed, slightest deviation in the dimensions of the pallet it being understood that changes in the precise 0 stone would seriously affect the running of the embodiment of the invention herein described watch. It is therefore necessary that the dismaybe made within the scope of what is claimed Y tance between the back face It) and the front without departing from the spirit of the invention. face ll be accurate and that the angle of the The invention is illustrated in the accompanyfront face II with the bottom 5 and the top 8 ing drawings in which: be absolutely accurate. The sloping section 9 or Figure 1 is a top plan view of the holder. lead angle is of no particular degree being used to Figure 2 is a detail of the holder greatly enpermit the insertion of the stone in the pallet larged. fork, the slightly less thickness at the back It) Figure 3 is an end view of the same detail as making the insertion easier. The rounded edge illustrated in Figure 2. I2 is formed to permit the watchmaker to use a Figure 4 is a side elevation of one of the matool against this edge to press the pallet stone chines showing the stones mounted in the holder into the fork. If this edge were sharp the pushing in contact with the lap. I tool might possibly chip and so mar the finished Figure 5 is a top plan view of a different lapping product.

Referring particularly to Figures 4, 5 and 6,

machine.

special types of machines are here shown for two of the grinding operations. Considering the machine shown in Figure 4 first, a base I3 supports a standard M which has pivotally mounted thereon a rocking arm IS on the axis I6. Mounted for rotation at the end of this arm is the holder I which is driven through the pulley l'L belt l8, pulleys l9 and 20, belt 2| and pulley 22, which in turn is driven by the controlmotor 23. i

The motor 23 is controlled by means of an oscillating rheostat 33 which drives the motor at con tinuously varying speeds so that therewlllbe no pattern formed during the polishing operation" between the pallet stones and the lap 24.

bearing 25 is driven at varying speeds through pulleys 26 or 21 which in turn"ar drivn *by a" motor not here shown. Micrometric means 28 i i I r in a, single operation, surface polishing the top for adjusting the level of the lap 24 is attached to the bearing 25 and serves to properly position the lap with regard to theholder I. j I:

The rocking arm l5 whi'ch supports the holder l at one end and a counter balancing weightfnot shown) attached to the ribbon 29 carries a level 30 to assist in adjusting the relative positions of the holder and lap 24. An electrical contact 3| is adapted to close an electric circuit thro ugh contact 32 which is micrometrically adjustable upon the completion of the grinding operation.

Referring particularly to Figures 5v and 6, a somewhat similar machine used for another one of the operations is shown mounted on a base 34 uponwhich two slide members 35 and 36 are carried. The member 36 rotatably. supportsfthe holder I which is mounted on a shaft connected to a pulley 31, which is drivenby means of a belt and motor not shown. The lap 38,is mounted for rotation in the bearings 39; and and is driven by means of the pulley. 4! through a belt and 0 motor (not shown). The pulley 4| is mounted on a sleeve42 which is in turn carriedby the shaft 43. Freely mounted on the shaft 43 isalpulley 44 having an integral cam surface 45 which engages a pin or cam follower 46 carried by the pulley 4|. Continued rotation of the pulley 44 by means of a belt and motor (not shown) causes movement of the lap 38 axially of the shaft 42, which moves the lap a small fraction against the edges 4! of the stones mounted in the holder of the operation.

- WhatYis claimed is:

ATmethod of finishing pallet stones of substantially parallelepiped form consisting in mounting 1151' that the sides of adjacent stones are substantially 5 parallel, cuttingall'of said stones by engagement witha diamond lap to a predetermined length aiplurality of'unfinished stones on radial lines so and exposed surface of said stones in another single operation, angle cutting'the free end of said stones to a surface conforming to a section of a'c onical surface, polishing all of said angled cut endsina single operation, bufiing 'th'e'upper most outer edge of all bf said stones with a resilient diamond lap and polishing the inward end of the top surface of all'of said stones' to form a lead angle 'in still another operation.

REFERENCES CITED The following references are of record in'tlie.

file 10f this patent:

UNITED STATES PATENTS 

